


What to Expect When You're Expecting

by SmolderingFlame



Category: South Park
Genre: Alpha Kenny, Alpha Kyle, Alpha/Beta/Omega Dynamics, Alpha/Omega, Angst, Bottom Stan Marsh, Crossdressing, Cults, Drama, Feminization, High School, M/M, Mpreg, Omega Stan, Out of Character, Pregnancy, Romance, Secret Identity, Superheroes, Teenage Drama, Top Kenny McCormick, Top Kyle Broflovski, Unplanned Pregnancy, mysterion - Freeform
Language: English
Status: In-Progress
Published: 2019-02-12
Updated: 2019-02-12
Packaged: 2019-10-26 19:13:46
Rating: Explicit
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 2,264
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17751833
Author URL: https://archiveofourown.org/users/SmolderingFlame/pseuds/SmolderingFlame
Summary: Stan Marsh didn't do stupid things. He always considered himself to be pretty boring, but, trouble seemed to have a way of finding him. This time the trouble came wrapped as a superhero.





	What to Expect When You're Expecting

**Author's Note:**

> Well, I've had Stan bottom with Kyle, Craig, and even Cartman, so, I think it's time Kenny got his turn!
> 
> I'm really excited to work on this one, I love Kenny, and as an avid comic book reader i'm very excited to write Mysterion! This does have the Alpha/Omega plot devices in it, though, the characters have already all presented by this point.
> 
> Kudos, comments, and suggestions (especially for the first chapter) are highly appreciated!
> 
> (But I'm a Football Player! and Bonded will still be getting usual updates)

_“I wear a mask. And that mask, it's not to hide who I am, but to create what I am. **”**_

****

Patrols had become a routine for him, a way for him to clear his head, and, a way for him to check on those he cared about the most. It had fucked up his sleeping schedule, his grades in school, and even some of his relationships, but, some things were bigger than his wants and his desires. He enjoyed the dark, lurking in the shadows, working under the cloak of night; it made him…mysterious… Well, he supposed that was what helped give him his persona.

 

Mysterion had often made the news.  Crazy things always seemed to happen in South Park, but, a real life superhero? That was almost too crazy for the sleepy mountain town. A masked figure was saving people from muggings, beatings, even murders. Everyone wanted to know who was behind the mask, but, no one had figured it out. No one had figured out it was just the latch key stoner kid who was accustomed to dying. He had even managed to keep it a secret from his friends. No matter how much he wanted to tell them, confide in them, seek solace in them, he couldn’t. Besides, they wouldn’t believe him, hell, they didn’t believe him when he told them he had died over and over again.

 

He sighed as he finished up at his own mobile home. One of the things he always did on his patrol was check in on his sister Karen. Karen was now a Freshman in highschool and things had gotten more complicated for her. She was now being brought into a world of sex and drugs, she needed a good influence, and their parents weren’t going to fucking do anything. Hell, they were barely around anymore. Nothing but no good junkies who were in and out of jail like a revolving door. It didn’t help Karen had yet to present. In their society, there were three different sub-categories one could be placed in, the elite, the strong, the masculine, the Alphas, like Kenny himself was. The ones who were mostly unchanged, who didn’t have to follow the harsh rules of their society, the Betas. And, the feminine, the child carriers, the submissive ones, the Omegas. After watching his sister grow, he feared she would become an Omega, making her even more of a target then she already was.

 

The other person he checked on every night during his patrol was a presented Omega, one of his oldest and dearest friends, a friend that he wished with all of his heart and soul was more than just a friend… He thought about him as he made his way towards the suburbs of South Park, towards the cookie cutter houses that were all pushed together. Inside one of those was the object of his affections, of his desires.

 

Everyone had been surprised when Stan Marsh had presented as an Omega. Kenny had been downright gobsmacked when he got the news. Stan always seemed like he would be the perfect Alpha, he was muscular, liked sports, was a flirt, and always had the confidence of one who would present as the elite of their society. But, that hadn’t been the case. Stan was an Omega, and with that came all the body changes, the society changes, the changes with how he was treated. It had been hard for him at first; Kenny had seen him cry when he was forced off the football team, when he had to wear feminine clothing, when his parents told him his romantic future was in their hands, not his. It had been tough, and, Kenny tried to be there as much as he could, but, he seemed constantly blocked by either Stan’s parents, who had labeled him as a bad influence, or, but fellow Alpha, Kyle, who had made his intentions very clear when it came to Stan. The pair had been Super Best Friends, and, everyone knew there was something more to them than just a mere friendship. Kyle had become so possessive and protective of Stan that it was hard to even see the brunette anymore by himself.

 

Maybe that was why the brunette had become one of his stops on his nightly patrols. Even if it was just checking in on him to make sure he wasn’t crying, that he was safe in his bed. Kenny knew he had feelings for Stan, romantic feelings. He was so beautiful, but, he had always been, even before he presented. He was gorgeous on the outside, but also, the inside. Stan loved animals, he loved the environment, and he always sought the best in people.

 

He shook his head to try and drive him out of his thoughts when he approached the Marsh family home. Slowly making his way towards the window that belonged to Stan, a strange smell was wafting from it. It smelled….sweet? It smelled like roses, like expensive perfume… The cloaked figure raised an eyebrow as he moved to peak into the window, his eyes going wide behind his mask.

 

Stan was on his bed, obviously nesting, letting soft moans escape his plump lips as he arched his back. It was obvious the Omega was in Heat.

 

Kenny bit his lower lip. He knew he had to get out of there. Yes he was superhuman, but, even he couldn’t control primal urges. As an Alpha, when he caught the scent of an Omega in Heat, especially one he was attracted to, he didn’t know if he could contain himself.

 

He groaned, trying as hard as he could not to open the window. He was almost ready to leave, until, a soft sensual moan caressed his ears. He found his hands on the window and slowly opening it, the sweet scent becoming stronger. He wanted to push back his cowl and show the brunette who he was, that he wasn’t a dangerous stranger, but, he knew he couldn’t.

 

Stan’s blue eyes went wide when he watched the masked figure come through his window. He didn’t know what to think, in the state he was in, his mind was already clouded. “W-Who…who are you?” He managed to ask, biting his lower lip as the figure stepped closer.

 

“I…don’t mean you any harm.” Mysterion said, holding up his hands. “I was just patrolling…I heard noises coming from your window and I wanted to make sure you were okay…” He added in his gruff voice.

 

“Wait…you’re the guy from the papers…and the news… The superhero…” Stan said, sitting up a bit. “You saved that dog from being beaten by those fucking assholes… I tried to stop them…but they wouldn’t…and then you showed up…kicked the shit out of them…” He said, a small smile crossing his plump lips. “You disappeared before I got a chance to thank you.”

 

“I don’t need thanks. Those fuckers got what was coming to them. I was just glad they didn’t turn on you, you could have gotten yourself hurt.” The figure said, making his way towards the bed. “They were looking at you…like they wanted to…mess around with you.”

 

Stan sighed a bit. “I know… It sucks being an Omega… I hate it so much… I know how to fight, but, no way I could take on a group of Alpha thugs…. They don’t find me intimidating, most of the time; they just want to fuck me…”

 

The superhero just cleared his throat, looking noticeably uncomfortable when he saw the blankets slide down, showing off a thick ivory bare thigh. God, Stan was barely wearing anything… It made since, he was in Heat, he was probably so hot….

 

“I should get going… I just wanted to make sure you were okay.” Mysterion said, quickly turning around, looking like he was about to leave from the window he entered from.

 

“No….wait…don’t go…” Stan said, moving to get up from his bed. He was only wearing an oversized Broncos jersey, his bare pale legs shining in the moonlight. He padded his way towards the hero and quickly grabbed his hand. “I…really want to thank you for what you did.” He breathed out. He was horny, so fucking horny, and because his father still hadn’t found a suitable mate for him, or, what Stan believed, an Alpha with enough money, he never was satisfied during a Heat. It wasn’t fair, if he was an Alpha in a Rut, they would have let him fuck like crazy… He deserved to have the same rights as everyone else. Sure, Kyle wanted sex, but, it was different with him, he was so demanding, he wanted things on his terms, not Stan’s… This guy he was a hero….

 

“I have to go…” The hero said, before finding himself nearly falling to his knees when a pair of luscious lips pressed against his. He couldn’t help but close his eyes, slip his tongue in, and explore the sweet flavors of the mouth he had dreamed about. Stan was pressing his body against his, mewling softly, running his nails down his back, how could he resist? He managed to pull away.

 

“You’re in Heat; you don’t know what you’re doing…”

 

“I know exactly what I’m doing.” Stan breathed out. “If you don’t want it…then leave… But…I’m giving you an invitation.” He said softly. “You’ve done a lot of good…someone should thank you for it.”

 

The masked figure groaned, wanting to do the honorable thing and turn away, but, finding it impossible. Instead, he leaned down and pressed his lips against the smaller brunette’s, slipping his tongue back in. He was rather well versed when it came to sex. He had been fucking even before he presented, and, the one he had always wanted was now in his arms, begging for him. He was but a man… He felt small hands grab his wrists and start pulling him towards the bed, before watching as the beautiful Omega fell backwards onto the plush surface, coquettishly spreading his shapely legs apart for him.

 

“What’s your name?” Mysterion asked, making it sound like he didn’t already know what it was.

 

“Stan.” The brunette said softly. “I don’t usually do these things but…I want to feel satisfied for once during a Heat…. It hurts so badly when I can’t get off… My parents….they only care about finding an Alpha for me that has money…they don’t care what I think….no one does…” He said, before finding a gloved finger press against his lips.

 

“I care what you think, and, if you really want this, I’m more than happy to give it to you.” The hero said, before starting to undo his pants. “You’re so beautiful… I’ve patrolled all over this city…and I’ve never seen anyone that could hold a candle to your beauty.” He admitted, letting the black pants fall to the ground. “I can’t help but get lost when I see you around town, always trying to save a wounded animal or a bird that’s fallen out of its nest.” He said, hoping that didn’t sound extremely creepy.

 

Stan just laughed in a breathy manner. “I didn’t realize I was so interesting a superhero took notice in me.” He said, reaching up towards the mask, only to have his wrists grabbed by large hands.

 

“No… You will open a world of trouble if you do that.” Mysterion said, placing the hands down and climbing over the curvy figure. “Some things need to be kept a secret.” He added, leaning down to press a kiss to the sweet lips.

 

And that was how it happened. He knew he shouldn’t have, he should have left, been the bigger person, but, it was impossible. Before Kenny even knew what he was doing he was inside his best friend, fucking him, taking in every sweet moan that came out of the brunette’s lips. Stan felt amazing, so warm and tight, he didn’t know if that was the Heat or just how amazing Stan felt in general. Things never crossed his mind as he thrust in and out of the moaning Omega. He never thought to think of things like condoms and birth control, it seemed pheromones had gotten the better of him, and Stan, Stan was the sweetest goddamn flower. He wondered if Kyle had gotten a chance to do this, if Stan even wanted him to do this? God, if Kyle found out…he’d go into a Rut and kill him…

 

Before he knew it, it was already ending. The brunette was moaning and crying out his persona’s name, writhing in pleasure underneath him. That was all it took to drive Kenny over the edge, and, he came inside the Omega, groaning and wishing he could just take off his mask and show Stan who he was.

 

When it was over and Stan was asleep, Kenny couldn’t help but stare at the beautiful figure for a moment. He was so beautiful, so delicate, so perfect. What had he just done?

 

Pulling up his pants he stole one more look at the Omega of his desires before making his way out of the window. They could just wrack this up as hormones getting the best of both of them. Stan would be with Kyle and Kenny would just have to long for the brunette from afar… That was just his life. There was no room for romance when it came to Mysterion.


End file.
